This invention pertains to exercise equipment, and particularly to equipment for developing specific foot, ankle and leg muscles for runners and joggers.
The act of running or jogging consists of a very specific motion repeated thousands of times per hour. This motion employs a particular group of muscles referred to as "prime movers," the muscles along the back of the leg and the thigh. Running regularly over a period of time causes overdevelopment of these prime movers. They become short, tight and inflexible. The antagonist muscles, those on the front of the leg, become relatively weak.
The simple cause of the problem is that the posterior muscles, or prime movers, are doing the work during running while the anterior, or antagonist muscles, are relative inactive. An imbalance of strength and flexibility is created between these two muscle groups. As the tendons, ligaments, and muscles of the foot and legs try to compensate for this imbalance, they are forced to work harder and in ways in which they were not intended. These factors are a primary cause of many common running injuries such as tendonitis, shin splints, and stress fractures.
The current state of the art in foot exercise equipment consists of machines or devices designed to provide resistance to a pushing or downward motion of the foot. This pushing or downward motion of the foot is accomplished through the efforts of the prime mover muscle group. This is the same muscle group utilized in the act of running. Use of these devices by a regular runner will further develop the prime mover muscle group, thus increasing both muscle imbalance and the risk of injury.